君は規則に従って行動しなければならない。

You must act in accordance with the rules.

君(きみ)は規則(きそく)に従(したが)って行動(こうどう)しなければならない。

Kimi wa kisoku nishitagatte kōdōshinakerebanaranai.

君 (きみ)

you; buddy; pal; monarch; ruler; sovereign; (one's) master

は (は)

topic marker particle; indicates contrast with another option (stated or unstated); adds emphasis

規則 (きそく)

rules; regulations; conventions

に従って (にしたがって)

in accordance with; according to; as X, then Y (e.g. as we age we gain wisdom, as wine matures it becomes more valuable, etc.)

行動 (こうどう)

action; conduct; behaviour; behavior; mobilization; mobilisation

Readings: クン、きみ、 -ぎみ

Meanings: mister, you, ruler, male name suffix

Reading: キ

Meanings: standard, measure

Readings: ソク、のっと.る

Meanings: rule, follow, based on, model after

Readings: ジュウ、ショウ、ジュ、したが.う、したが.える、より

Meanings: accompany, obey, submit to, comply, follow, secondary, incidental, subordinate

Readings: コウ、ギョウ、アン、い.く、ゆ.く、 -ゆ.き、 -ゆき、 -い.き、 -いき、おこな.う、おこ.なう

Meanings: going, journey, carry out, conduct, act, line, row, bank

Readings: ドウ、うご.く、うご.かす

Meanings: move, motion, change, confusion, shift, shake